“The U.S. Antarctic Program expresses its gratitude to their Argentine colleagues for their willingness to help,” The National Science Foundation’s Office of Polar Programs said in a statement.

All five Americans were reported to be in good health.

The four scientists, led by Earth science researcher Alex Simms of UC Santa Barbara and a National Science Foundation support contractor from Colorado, have been conducting research on Joinville Island, off the north eastern tip of the Antarctic Peninsula.

They requested help from Argentina when it became clear the nearest U.S. vessel, Laurence M. Gould, was unable to break through the thick sea ice to get to them.

The group is now planning to return to Punta Arenas, Chile, where the U.S. Antarctic Program headquarters is located.